Plane Crash Exposes Seat Belt Differences02:40

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The Asiana Airlines flight that crashed in San Francisco had different seat belts for different classes of passengers: lap belts in economy and three-point seat belts in first class.

So why didn't every seat have the three-point harnesses — the type found in cars?

The thing with restraint systems is, the more restraints you have, the better off you're going to be in an impact situation.

Anthony Brickhouse

"In the general aviation world, three-point seat restraints are very common," Anthony Brickhouse, an associate professor of aerospace and aviation safety at Embry Riddle Aeronautical University, told Here & Now. "They are less common in the commercial aviation world. The thing with restraint systems is, the more restraints you have, the better off you're going to be in an impact situation."

While the three-point belts are the obvious choice in terms of safety, there are other factors in choosing restraints for commercial airlines.

"Financial considerations are always something that have to be taken into consideration. Passenger comfort is also something that has to be taken into consideration. But from my perspective, every day you get in your personal vehicle you have on a three-point harness. So for me, having a three-point harness in an airliner would not be any level of discomfort," said Brickhouse.

The evolution in airline safety has already gone past the three-point seat belt. Some flight training aircraft are also equipped with airbags.

"In the event of an impact, the airbag would come out almost like it would in your passenger vehicles. So basically it would cushion the blow, and anything we can do to cushion the blow for passengers is going to increase the likelihood of survivability."

With the ongoing investigation of what caused the Asiana Airlines flight to crash land, new safety standards may emerge to help prevent future crash deaths and injuries.